Jack



Sept. 18, 1928.

- F. M. AYCOCK JACK Filed Oct. s, 1927 INVENTOR ATTOR N EY WITNESS:

Patented Sept. 18, 1928.

entree @WWQE FRANCIS 1V1. AYCGCK, OF SOLDIERS HOME,

ONE-HUNDREDTHS T0 JAMES MARSH, FORNIA.,

JACK.

Application filed October 3, 1927. Serial No. 223,767.

This invention relates to scaffold jacks, and its general object is toprovide a scaffold jack that receives the cable of a movable scaffoldt'or holding. the scaffold at any desired height in a sate and securemanner. and will operate the scaffold for raising and lowering the samewith very little effort on the part of the operator.

A further object: of the invention is to provide a scafl old jack thatextremely simple in construction, inexpensive to manufacture, strong andsturdy. light in weight and cfiicient in operation and service.

This invention also consists in certain other features of constructionand in the combination and arran ement of the several parts, to behereinafter fully described, illustratcd in the accompanying drawingsand specifically pointed out in the appended claims.

In describing my invention in detail, reference will be had to theaccompanying drawings wherein like characters denote like orcorresponding parts throughout the scveral views. and in which:

Figure 1 a. side elevation of the jack forming the subject matter of thepresent invention and showing the scaffold cable applied thereto.

Figure 2 is a front elevation thereof.

Referring to the drawings in detail the numeral 1 indicates thebodyqalate of the jack and which has secured thereto through the mediumof rivets or other like securing means a frame which is formed from asingle strip of material and includes a substantially U-shaped portion 2which terminates at its lower end in an ear 3 while its opposite endextends upwardly in an upright 4 and terminates in a right angle bentend 5 which is provided with an opening through which passes thescaffold cable A and acts as a guide therefor as will be readilyapparent.

Secured to the lower end of the body plate are the upper ends of the ti-shaped strap 6 for accommodating-the main beam oi the. scadold which isindicated by the letter B.

Mounted in bearing openings formed in the body plate 1 and Ushapedportion of the frame is a shaft 7 which I term the drive shaft, andsecured to this drive shaft is a gear 8 which is arranged in constantmesh with a gear 9 and a pinion 10. The gear 9 plate as best shown inFigure 2 of the draw- 1 ings. The pinion 10 is secured to a stub shart12 which has one end also projecting beyond the outer face of the bodyplate 1.

Keyedto the projecting end of the stub shaft 11 a steel flange pulley 13which is provided with a cable receiving part preferably formed fromwood, and the inner flange 14 thereof is provided with ratchet teeth 15.Pivotally mounted on the body plate is a pawl 16 which cooperates withthe ratchet teeth in a manner as best shown in Figure 1 of the drawings.The cable A is trained about the steel flange pulley as best shown inFigure 2, and extends downwardly to be received between and in thegrooves 17 and 18 of gears 19 and 20. The gear 19 is carried by the stubshaft 12 while the gear 20 is mounted for rotation on a headed pin 21. Aguide pulley 22 is provided for said cable and is mounted for rotationon the body plate 1 above the flanged pulley.

The gear 19 is adjustable with respect to the gear 20 and in order toaccomplish this ad ustment, the stub shaft 12 is mounted in slots formedin the body plate and U-shaped portion and is journaled through anopening formed in a substantially L-shaped strip 23 wh ch has a setscrew 21 threadedly received in its outer portion as best shown inFigure 1 and engageable with the edge of the body strip, so that uponrotating the set screw. it will be obvious that the gear 19 can be movedas desired to tension the cable accordingly. Fixed to the drive shaft 7is a crank handle 25 which when rotated will rotatethe gear 8accordingly and impart motion to the gear 9 and pinion 10. The gear 9will operate the steel flanged pulley 13 and cause the cable A to traveltherealoout as will be apparent which will result in the raising orlowering of the scaffold, it of course depending upon which way thecrank handle 25 is rotated.

From the above description and disclosure of the drawings, it will beobvious that l have provided jack for cable operated scafiolds that isextremely easy to operate and due to the fact that the cable is arrangedbetween grooved gears with one of said gears mounted for adjustment withrespect to its companion gear, the tension of the cable can be varied inaccordance with the operators desires, and this construction will alsoretain the scaffold in fixed position and prevent the cable from movingeven if the pawl 16 is arranged to inoperative position.

It is thought that the foregoing description that the advantages andnovel features of my invention Will be readily apparent;

I desire it to be understood that I may make changes in the constructionand in the combination and arrangement of the several parts, providedthat such changes fall within the scope of the appended claims.

What I claim is: 1. A scafl'old jack scribed comprising a ho of thecharacter dedy plate having a right angle bent upper end formed withanopening, a 'frame secured to said body plate, shafts journaled insaid'body plate and frame, a crank handle secured to one of said shafts,gears cured to said shafts andgbeing arrangedf itconstant mesh, a pulleysecured to one of said shafts and receiving a cable of the scaffold,ratchet means included in said pulley, a guide pulley receiving saidcable and together with the openingof the upper end of the body plateprovide guiding means for saidtcable, and cable tensioning means carriedby said body plate.

2. A movable scaffold jack of the character described comprising a bodyplate, a frame secured to said body plate and including a U-shapedportion, a shaft journaled in said U-shaped portion and body platerespectively, a""shaft disposed upon opposite sides of the shaft firstmentioned and also being journaled accordingly, a steel flangedpulleysecured to one of the shafts last mentioned and receiving a cableof the cafl'old, ratchet teeth formed with one of he flanges of thepulley, a pawl pivoted to the body plate and engageable with the ratchetteeth, guide means for said cable and carried by said body plate andframe, a grooved gear secured to one of said shafts, a second groovedgear cooperating with the grooved gear first mentioned and both of saidgrooved gears receiving said cable thcrebetween and in the groovesthereof, means for moving one of said grooved gears with respect-to theother grooved gear for tensioning the cable means for rotating thepulley and first mentioned grooved gear from said first mentioned shaftand a handle crank for rotating said first mentioned shaft.

3. A movable scaffold jack'of the character described comprising a bodyplate, a frame secured thereto, grooved gears mounted for rotation andcarried by said body plate, a steel flange pulley mounted for rotationand adapted to have a cable of the scaffold trained thereabout, meansfor guiding said cable, means for operating said pulley and groovedgears simultaneously, means for adjusting one of said grooved gears withrespect to the other, ratchet means for said pulley and including teethformed on one of the flanges thereof, and a scaffold beam strap securedto said body plate.

In testimony whereof I aflix my signature.

FRANCIS M. AYCDCK.

